Display panel having a plurality of display registers

ABSTRACT

A display panel includes a plurality of display cells arrayed in rows and columns, with electrodes coupled to the cells in such a way that a plurality of rows of characters can be displayed, with blank spaces being provided between the rows of characters. Electrodes may be provided in these blank spaces to perform an auxiliary function such as a keep-alive function.

United States Patent Caras [4 1 Apr. 4, 1972 5 DISPLAY PANEL HAVING A[56] References Cited [721 Bernard Came Princeton 2,847,615 8/1958Engelbart 1 5/84.6 Assignee2 Burroughs Corporation Detroit l Engelbart[22] Filed: Mar. 19, 1970 Primary Examiner-John Kominski AssistantExaminer-Palmer C. Demeo [21 1 Appl' Anomey-Kenneth L. Miller and RobertA. Green 52 us. 01. ..313/19s, 313/109.5, 313/220, [57] ABSTRACT315/84.6, 315/1 TV A display panel includes a plurality of display cellsarrayed in [51 Int. Cl. ..H0lj 61/54 rows and columns, with electrodescoupled to the cells in such [58] Field of Search ..3l5/84.6, 169 R, 169TV; a way that a plurality of rows of characters can be displayed,

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ATTORNEY Patented April 4, 1972 3 Sheets-Sheet 5 S m Q m l M m V d m w ag 6Q I09 mom: Q09 mow? f9 m 0m 1 20m; zow 087 @09 Wow; 7 om mwr mm v9 0%mm? S Q Q Q Q Q Q Q Q Q Q Q Q omT Q Q Q Q Q Q Q Q Q Q Q Q oi 3 Q Q 3 3 3Q Q Q Q Q \[Owr Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q Q ATTORNEYDISPLAY PANEL HAVING A PLURALITY F DISPLAY REGISTERS BACKGROUND OF THEINVENTION Display panels of various types including a plurality ofdisplay cells arrayed in rows and columns have been known for some time.However, until recently, these devices have not been commerciallyavailable.

Display panels are useful because they provide a compact means fordisplaying information, and use can be made of panels of all sizes from,for example, postage stamp size to wall size. A particularly usefulpanel is one which can be used to display several rows of informationsimultaneously. However, at the present time, such a multi-row ormulti-register display panel is not known.

SUMMARY OF THE INVENTION Briefly, a display panel embodying theinvention comprises a gas-filled envelope and an assembly thereinincluding a plurality of gas-filled cells and a plurality of electrodeswhich perform different functions. The various electrodes and theassociated structural elements are interrelated and arranged to displaya plurality of registers of information simultaneously.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view of a panel embodyingthe invention and illustrating the capability thereof of displayingseveral registers of information;

FIG. 2 is a plan view of a portion of a display panel embodying theinvention;

FIG. 3 is a perspective view of a portion of a panel embodying theinvention showing a portion thereof which is associated with the portionshown in FIG. 2;

FIG. 4 is a sectional view along the lines 44 in FIG. 2 but includingall other parts of the panel not shown in FIG. 2;

FIG. 5 is a sectional view along the lines 55 in FIG. 2 but includingall other parts of the panel not shown in FIG. 2;

FIG. 6 is a sectional view along the lines 6-6 in FIG. 2 but includingall other parts of the panel not shown in FIG. 2;

FIG. 7 is a sectional view along the lines 77 in FIG. 2 but includingall other parts of the panel not shown in FIG. 2; and

FIG. 8 is a sectional view along the lines 8-8 in FIG. 2 but includingall other parts of the panel not shown in FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENTS A display panel 10 describedherein is a thin, flat, sheetlike member which may have substantiallyany desired size and shape from, for example, postage stamp size to wallsize, and it may include substantially any number of display cells. Thepanel may also include any suitable ionizable gas such as neon, argon,xenon, etc., singly or in combination, with a vapor of a metal such asmercury usually included in the gas to minimize cathode sputtering. Thepanel, as illustrated in FIG. 1, displays three rows of characters, witheach character being made up of a plurality of dots of light generatedby gas-filled display cells and with a space being provided between eachrow of characters. Each row of characters is known as a register. Ofcourse, the number of registers and the number of characters displayedper row may be readily increased in accordance with the principlesdescribed herein.

Ordinarily, display devices which use dots of light to form charactersutilize a matrix of at least 7 X7 dots to form a character. Such amatrix may also be used in panel 10 in actual practice. However, forpurposes of illustration, a smaller number of dots is shown anddescribed.

The display panel 10, embodying the invention, includes a bottom plateof an hermetic, dielectric material, such as glass or ceramic, which hasa top surface 30, a bottom surface 40, an upper edge 50, a lower edge60, a left edge 70, and a right edge 80. The plate 20 has a plurality ofparallel slots or channels 90 (A to N) formed in the top surface 30thereof. For purposes of illustration, the panel is oriented so that theslots extend horizontally across plate 20 from the left edge 70 to theright edge 80.

The array of slots 90 is suitably positioned between the upper and loweredges of plate 20, with the first slot 90A being closest to the upperedge 50 of the plate, and the last slot 90N being closest to the loweredge 60 of the plate.

The slots 90 are all identical in size, shape, width, depth, etc., andcan be made by any suitable mass production process. For purposes ofillustration, three slots 90 are used in forming a row or register ofcharacters 12, in a manner to be described, and the plate includes threegroups of three slots 90 for displaying three rows of characters with,say two, non-display slots 90 between each group of three display slots.The two non-display slots provide spacing between each row ofcharacters.

In panel 10, slots 90A, B, C form one display register; slots 90D and Eform non-display, inter-register slots; slots 90F, G, H form the nextdisplay register; slots 90] and K form the next non-display,inter-register slots; and slots 90L, M, N form the third displayregister.

In one embodiment of the invention and for a purpose to be described,the inter-register slots 90D, E, .I, and K are terminated near theleft-hand edge of plate 20 by a mass of glass 93 or the like depositedtherein. These slots thus terminate near the left edge 70 of the plate20 and of the panel, this being the end at which a scanning operationoriginates in one mode of operation of the panel to be described.

Electrodes 110, which are used as counting or scanning anodes in onemode of operation of the panel, are seated in each of the three displayslots 90 of each character display register, and these electrodes extendbeyond the left and right edges of plate 20 and of the panel 10 so thatthey are accessible outside the panel. Electrodes 1 10 are preferablyindividual wires set into the slots; however, they may also be plated,evaporated, or otherwise formed in the slots. The electrodes 110, ifseparate wires, might also be secured in the slots 90 by means of acement such as a fused glass frit or the like. In one embodiment of theinvention, an auxiliary wire electrode 120, if needed for a purpose tobe described, is seated in each of the inter-register slots 90D, E, .I,and K, and these originate at the obstruction 93 and extend leftwardbeyond the left end 70 of the plate 20.

Panel 10 also includes a center sheet or plate of a dielectric material,the same as the material of plate 20 if desired, which is seated onbottom plate 20 and has a top surface 132, a bottom surface 134, anupper edge 136, a lower edge 138, a left edge 140, and a right edge 142.The sheet 130 is provided with a plurality of rows and columns ofapertures or holes 144, and the bottom surface 134 thereof is providedwith a plurality of generally rectangular, parallel, vertical slots 150Ato P. Slots 150 all have the same width and depth and extend along sheet130 from the lower edge 138 to the upper edge 136. The slots 150 areoriented at 90 to each of the slots 90, and thus, in effect, cross eachof the slots 90 in the bottom plate 20. The array of slots 150 issuitably positioned between the left and right edges 140 and 142,respectively, of center sheet 130, with the first slot A (FIG. 3)considered to be the first slot positioned near the left edge 140 ofsheet 130, and the last slot 150P being positioned close to the rightedge 142 of sheet 130.

In plate 130, the holes 144 are arrayed in rows and columns, with thecolumns of holes aligned with and overlying each of slots 150C to 150Pbut not slots 150A and B. The rows of holes 144 are generally alignedwith and overlie all of the slots 90. The holes 144 are all identical,and the slots 150 are all identical, and each may be made by anysuitable mass production process. Holes 144 are not required over theinter-register, non-display slots 90. However, in mass productionmanufacture of the plate 130, it is as easy to provide them as not.

A plurality of electrodes A to N, operated as scanning cathodes, areseated in the slots 150C to P, respectively, in sheet 130. The scanningcathode electrodes 160 are metal strips which substantially fill theslots 150 and extend along the entire length thereof and beyond theupper and lower edges of plate 130. The cathodes 160 are oriented at 90to the anodes 110, and each cathode crosses each anode. Each electrode160 is provided with a plurality of tiny apertures 162 disposed alongits length, with each aperture 162 being generally centrally positionedover a slot 90 (FIG. 4) in bottom plate and beneath a hole 144 in centerplate 130. Each column of cathode apertures 162 is aligned with a columnof holes 144, and the rows of apertures 162 formed by the adjacentcathodes are aligned with the rows of holes 144. Apertures 162 are notrequired over inter-register slots 90. The cathodes 160 are identical insize and shape and can be made by any suitable mass production process.

An unapertured cathode strip electrode 161, which is somewhat narrowerthan the cathodes 160 and the slots 150, is seated in slot 1508, and astrip electrode 163 which is identical to cathodes 160, but does nothave apertures, is seated in slot 150A. The cathode electrodes 160 andelectrodes 161 and 163 need not be seated in slots in plate 130, ifdesired.

A second group of wire electrodes 180, used as display anodes, areseated on or in the top surface 132 of plate 130, one for each wireelectrode 110 in plate 90. Each electrode 180 is parallel to and alignedwith an electrode 110. Each electrode 180 is generally aligned with andoverlays a row of holes 144 in center sheet 130. The electrodes 180 neednot be centered over the holes; they need only communicate with the gasin the holes. Thus positioned, electrodes 180 are parallel to and arealigned with wire electrodes 110 in plate 20.

A transparent cover or viewing plate 190 of a dielectric material suchas glass completes the panel and is seated on center plate 130. The wireelectrodes 180 might be seated in slots in the bottom surface of topplate 190, as shown in FIGS. 6 to 8, if desired. In the completed panel10, the three plates 20, 130, and 190 are hermetically secured togetherby a seal 200 formed along their adjacent edges by any suitable meanssuch as a fused glass frit (Pyroceram) or the like.

The gas used in panel 10 is introduced in any suitable manner, forexample, by means ofa bell jar or by means of a tabulation 203 (shownonly in FIG. 4), secured to bottom plate 20.

As described, panel 10 includes, in each register, a lower layer of gascells 210 which are called counting or scanning cells (FIGS. 2, 4, and8) arrayed in rows and columns, with each cell comprising a portion ofthe apertured strip cathode electrode 160 above it, the anode electrode110 below it and the gas volume between these electrodes in slot 90.Thus, each column of counting cells is defined by each cathode 160 andits crossing of a slot 90 and the associated portion of a counting anode110. As seen in FIG. 2, there are 12 columns of counting or scanningcells 210, and, for purposes of description, the first column isassociated with cathode 160A, the second column with cathode 160B, thethird column with cathode 160C, etc. Each column of scanning cells 210communicates with the adjacent column, that is, each scanning cell inone column communicates with the corresponding cell in the adjacentcolumn, through the associated slot 90.

The panel 10 also includes an upper layer of gas cells 220, known asdisplay cells, associated with and positioned above and generallyaligned with, the counting cells 210. Each display cell 220 (FIGS. 4, 5,and 8) is made up of a portion of a cathode 160, the associatedgas-filled hole or cell 144 in center sheet 130, and the associatedportion of upper anode electrode 180. As with the counting cells, thereare also 12 columns of display cells 220, each associated with a cathode160, with the first column associated with cathode 160A, etc.

The panel 10 also includes a column of auxiliary cells 224, which areknown variously as starter cells, reset cells, particlesupply cells, orglow-spreading cells (FIGS. 2 and 7), and these cells supply excitedparticles to facilitate the turn-on of the first column of countingcells 210 associated with cathode 160A at the beginning of a scanningcycle, to be described.

For convenience, cells 224 will be called reset cells. These reset cellsare arrayed in a column to the left of the first column of countingcells and communicating therewith through slots A, B, C, and F, G, H,and L, M, N. Cells 224 are constituted by the cathode strip 161 and theportion of each anode which it crosses and the gas volume in the slots90 therebetween.

Generally, in operation of a display panel such as panel 10,particularly in a scanning type of operation (see commonly assignedpatent application Ser. No. 850,984, filed Aug. 19, 1969) wherein thecolumns of scanning cells are fired in turn and in series beginning atthe left end of the panel and proceeding to the right end thereof, it iscustomary to provide the reset cells 224 to facilitate the turn-on ofthe first column of scanning cells which are associated with displaycells. Other arrangements are known for providing and operating suchreset cells (see commonly assigned patent application Ser. No. 881,024,filed Dec. 1, 1969). In addition, it may be desirable to provideauxiliary cells, known as keep-alive cells, for operation of the resetcells. Various arrangements are known for providing keep-alive cells,and one of these is described and claimed in applicant's copending andcommonly assigned application Ser. No. 6,839, filed Jan. 29, 1970.

In another suitable arrangement, referring to panel 10, the electrodesin the inter-register slots 90 and the first electrode 163 may be usedto provide a keep-alive function. The keep-alive cells 228 formed bythese electrodes communicate with the reset cells through spaces aroundthe masses 93 and thereby provide excited particles to facilitate theoperation of the reset cells.

Generally, a keep-alive function is achieved by having the keep-alivecells always ON and fired to maintain a constant supply of excitedparticles for the reset cells. In this type of operation, electrode 163may be operated as a cathode, and electrodes 120 as anodes, or viceversa.

In the description of the operation of the invention set forth below,reference is made to scanning or glow transfer" from cell to cell orcolumn to column. Several different types of actions occur includingglow transfer from the keep-alive cells 228 to the reset cells 224, fromthe reset cells 224 to the scanning or counting cells 210, from ascanning cell to a scanning cell, and from a scanning cell to a displaycell 220. The exact mechanism by which each such operation occurs cannotbe described with complete certainty; however, the operations mayinvolve actual transfer of a mass of glowing ionized gas, or thediffusion of excited particles including metastable states whichfacilitate a new firing of an OFF cell, or both mechanisms may beinvolved.

In operation of the panel 10, the keep-alive cells 228 communicate, bymeans of the diffusion of excited particles, with the reset cells 224through slots 90D and E and slots 90J and K. Excited particles alsodiffuse along keep-alive cathode 163 and in the spaces between thiscathode and its slot A and reach reset cathode 161 by way of others ofthe slots 90. As noted, the keep-alive cells are always ON, and, when itis desired to turn on the reset cells 224, operating potential is applied to the reset cathode 161 and to all of the anodes 110. With theaid of excited particles from the keep-alive cells, glow spreads alongthe entire length of the reset cathode 161 in the spaces (FIG. 4) oneither side thereof.

When the reset cells 224 have fired, the first column of counting cells210 can be fired with the aid of excited particles generated in thereset cells and able to diffuse to the first column of counting cellsthrough slots 90A, B, C and 90F, G, H and 90L, M, N. An arrangement forusing reset cells to fire counting cells is described and claimed incopending and commonly assigned application Ser. No. 791,208 filed Jan.7, 1969. In addition, methods and apparatus including circuits forscanning columns of counting cells and energizing display cellstherefrom are described and claimed in the above-mentioned applicationSer. No. 850,984. These circuits are not shown here. In a typicalscanning operation, the scanning or counting anodes 110 are connected todriver circuits for applying generally positive operating potentialthereto, and each of the cathodes 160 is connected to a driver circuitfor applying generally negative operating potential to each,sequentially, to cause each column of counting cells 120 to fire andglow. The firing of each column of counting cells, after the first hasbeen fired, is facilitated by the diffusion of excited particles throughthe slots 90 from ON counting cells to the adjacent OFF counting cellsto be fired. The columns of counting cells 210 are fired sequentiallyfrom left to right, as seen in FIG. 2. This sequential firing of thecolumns of lower counting cells 210 is carried out cyclically from leftto right. Each time the last column of counting cells at the right-handedge of the panel is reached, the column of reset cells 224 at theleft-hand edge of the panel is turned on again, with the aid of thekeep-alive cells, and the above-described cycle is repeated. If desired,circuit means may be provided to sense the turn-on of the last column ofcounting cells 120 and automatically turn on the reset cells to startthe cycle again.

When it is desired to fire cells 220 in the upper layer to provide adisplay of information or the like, generally positive operatingpotentials are applied to the proper upper anodes 180 associated withthe cells 220 to be fired and glow transfers from the associated lowercells 210 through the apertures 162 in cathode electrodes 160 to theupper cells where the glow can be viewed through top plate 190. Asdescribed above, the glow transfer is facilitated by the presence ofexcited particles in each of the lower counting cells 210 when it isfired. By properly synchronizing the switching of the cathodes with theapplication of information signals to the display anodes 180, thedesired characters are displayed in each register.

It is clear that modifications may be made in the panels describedwithin the scope of the invention. For example, although the panel asdescribed is scanned from left to right, the scanning may be effected inother ways, and this might require a rearrangement of parts. Inaddition, in some modes of operation, keep-alive cells may not berequired, and, in some cases, both keep-alive cells and reset cells maynot be needed.

In general, the drawings are not intended to be dimensionally exact,and, in a typical display panel embodying the invention, the top plate190 and bottom plate are about one-fourth inch in thickness, and thecenter plate 130 is about 40 mils in thickness. In addition, in plate20, slots 90 are 10 mils wide and mils deep, and electrodes 110 and 120are 5 mils in diameter. ln plate 130, slots 150 are 36 mils wide and 1to 3 mils deep, with cathodes 163 and 160 having approximately the samedimensions. The holes 162 in the cathodes 160 are l to 3 mils indiameter, the holes 144 in plate 130 are 18 to 24 mils in diameter andmils deep, and electrodes 180 are about 3 mils in diameter.

What is claimed is:

l. A display panel comprising a gas-filled envelope including a bottomplate, a center plate, and a top plate, all being of dielectric materialand hermetically sealed together along their adjacent edges, said bottomplate having a top surface, a bottom surface, a left edge, a right edge,an upper edge, and a lower edge,

said bottom plate also having a plurality of first parallel identicalslots extending into said plate from said top surface and extendingalong the entire length of said plate,

first electrodes seated in several groups of said first slots andextending along the entire length thereof and beyond both ends thereof,said groups of first slots comprising display registers,

each of said several groups of said first slots being separated by aninter-register slot which does not contain one of said first electrodesin it,

said center plate having a top surface, a bottom surface, a left edge, aright edge, an upper edge, and a lower edge,

a plurality of second electrodes disposed between said bottom plate andsaid center plate and oriented at an angle to said first electrodes,each second electrode crossing each first electrode, each crossingdefining a cell which can be fired by potentials applied to the twoelectrodes at the crossing,

a plurality of holes formed in said center plate and arrayed in rows andcolumns, each column of holes being aligned with one of said secondelectrodes, and

a plurality of third electrodes aligned with the rows of said holes anddisposed between said top plate and said center plate, each thirdelectrode also being aligned with one of said first electrodes.

2. The panel defined in claim 1 wherein an auxiliary electrode is seatedin said inter-register slot.

3. The panel defined in claim 1 wherein said inter-register slot isblocked by an insulating mass and an auxiliary electrode is seatedtherein.

4. A display panel comprising a gasfilled envelope including a bottomplate, a center plate, and a top plate, all being of dielectric materialand hermetically sealed together along their adjacent edges,

said bottom plate having a top surface, a bottom surface, a left edge, aright edge, an upper edge, and a lower edge,

said bottom plate also having a plurality of first parallel identicalslots extending into said plate from said top surface and extendingalong the entire length of said plate,

first anode electrodes seated in several groups of said first slots andextending along the entire length thereof and beyond both ends thereof,said groups of slots being associated with display registers,

each of said several groups of said first slots being separated by aninter-register slot which does not contain one of said first electrodes,

said center plate of dielectric material having a top surface, a bottomsurface, a left edge, a right edge, an upper edge, and a lower edge,

a plurality of electrodes comprising cathodes disposed between saidbottom plate and said center plate and oriented at to said firstelectrodes, each cathode electrode crossing each first electrode, eachcrossing defining a cell which can be fired by potentials applied to thetwo electrodes at the cell crossing,

a first auxiliary cathode electrode adjacent to the first cathode insaid array of cathode electrodes,

auxiliary electrode means adjacent to said first auxiliary electrode andadapted to be held ON to provide a constant source of excited particlesfor said first auxiliary electrode,

a plurality of holes formed in said center plate and arrayed in rows andcolumns, each column of holes being aligned with one of said pluralityof cathode electrodes, and

a plurality of second anode electrodes aligned with the rows of saidholes and disposed between said top plate and said center plate, eachsecond electrode also being aligned with one of said first anodeelectrodes.

5. The panel defined in claim 4 wherein each of said plurality ofcathode electrodes comprises a metal strip which has a series ofapertures extending along its length, each said aperture communicatingwith a hole in said center plate.

6. The panel defined in claim 4 wherein another electrode is seated insaid inter-register slot.

7. The panel defined in claim 4 wherein said inter-register slot isblocked by an insulating mass and another electrode is seated therein.

1. A display panel comprising a gas-filled envelope including a bottomplate, a center plate, and a top plate, all being of dielectric materialand hermetically sealed together along their adjacent edges, said bottomplate having a top surface, a bottom surface, a left edge, a right edge,an upper edge, and a lower edge, said bottom plate also having aplurality of first parallel identical slots extending into said platefrom said top surface and extending along the entire length of saidplate, first electrodes seated in several groups of said first slots andextending along the entire length thereof and beyond both ends thereof,said groups of first slots comprising display registers, each of saidseveral groups of said first slots being separated by an inter-registerslot which does not contain one of said first electrodes in it, saidcenter plate having a top surface, a bottom surface, a left edge, aright edge, an upper edge, and a lower edge, a plurality of secondelectrodes disposed between said bottom plate and said center plate andoriented at an angle to said first electrodes, each second electrodecrossing each first electrode, each crossing defining a cell which canbe fired by potentials applied to the two electrodes at the crossing, aplurality of holes formed in said center plate and arrayed in rows andcolumns, each column of holes being aligned with one of said secondelectrodes, and a plurality of third electrodes aligned with the rows ofsaid holes and disposed between said top plate and said center plate,each third electrode also being aligned with one of said firstelectrodes.
 2. The panel defined in claim 1 wherein an auxiliaryelectrode is seated in said inter-register slot.
 3. The panel defined inclaim 1 wherein said inter-register slot is blocked by an insulatingmass and an auxiliary electrode is seated therein.
 4. A display panelcomprising a gas-filled envelope including a bottom plate, a centerplate, and a top plate, all being of dielectric material andhermetically sealed together along their adjacent edges, said bottomplate having a top surface, a bottom surface, a left edge, a right edge,an upper edge, and a lower edge, said bottom plate also having aplurality of first parallel identical slots extending into said platefrom said top surface and extending along the entire length of saidplate, first anode electrodes seated in several groups of said firstslots and extending along the entire length thereof and beyond both endsthereof, said groups of slots being associated with display registers,each of said several groups of said first slots being separated by aninter-register slot which does not contain one of said first electrodes,said center plate of dielectric material having a top surface, a bottomsurface, a left edge, a right edge, an upper edge, and a lower edge, aplurality of electrodes comprising cathodes disposed between said bottomplate and said center plate and oriented at 90* to said firstelectrodes, each cathode electrode crossing each first electrode, eAchcrossing defining a cell which can be fired by potentials applied to thetwo electrodes at the cell crossing, a first auxiliary cathode electrodeadjacent to the first cathode in said array of cathode electrodes,auxiliary electrode means adjacent to said first auxiliary electrode andadapted to be held ON to provide a constant source of excited particlesfor said first auxiliary electrode, a plurality of holes formed in saidcenter plate and arrayed in rows and columns, each column of holes beingaligned with one of said plurality of cathode electrodes, and aplurality of second anode electrodes aligned with the rows of said holesand disposed between said top plate and said center plate, each secondelectrode also being aligned with one of said first anode electrodes. 5.The panel defined in claim 4 wherein each of said plurality of cathodeelectrodes comprises a metal strip which has a series of aperturesextending along its length, each said aperture communicating with a holein said center plate.
 6. The panel defined in claim 4 wherein anotherelectrode is seated in said inter-register slot.
 7. The panel defined inclaim 4 wherein said inter-register slot is blocked by an insulatingmass and another electrode is seated therein.